One proposed technique applied to a vehicle equipped with an engine is, in the event of incompletion of learning a control demand for feedback control of at a throttle opening for regulation of an idling rotation speed of the engine to a target idling rotation speed, to prohibit stopping the engine until completion of the learning (see, for example, Japanese Patent Laid-Open Gazette No. H11-107834). This technique does not stop the engine of the vehicle until completion of learning the control demand for regulation of the idling rotation speed. This proposed technique may be applied to a hybrid vehicle with less opportunities of learning the control demand for regulation of the idling rotation speed. In such application, setting an appropriate learning value and adequate reflection of the learning value on the feedback control of the throttle opening attain favorable idling operation of the engine.